Andrea WalshAndrea Walsh44° Mr. Collins° Mr. Collins

• Fishes are aquatic vertebrates that are characteristized by Fishes are aquatic vertebrates that are characteristized by paired fins, scales, and gills. paired fins, scales, and gills.

Evolution of FishesEvolution of Fishes

The evolution of The evolution of jaws and the jaws and the evolution of evolution of paired fins were paired fins were important important developments developments during the rise of during the rise of fishesfishes Priscacara.

The First FishesThe First Fishes

The first fishes were odd-The first fishes were odd-looking, jawless creatures looking, jawless creatures whose bodies were whose bodies were armored with bony armored with bony plates.plates.

They lived in oceans They lived in oceans during late Cambrian during late Cambrian period, about 510 million period, about 510 million years ago.years ago.

Fishes kept this armored, Fishes kept this armored, jawless body plan for 100 jawless body plan for 100 million years.million years.

Priscacara pealei

Priscacara liops

The Ages of FishesThe Ages of Fishes

During the Ordovician and Silurian During the Ordovician and Silurian periods about 505 to 410 million periods about 505 to 410 million years ago, fishes underwent a years ago, fishes underwent a major adaptive radiation.major adaptive radiation.

The species to emerge from the The species to emerge from the radiation ruled the seas during the radiation ruled the seas during the radiation period (Age of Fishes).radiation period (Age of Fishes).

These fishes were jawless with little These fishes were jawless with little armorarmor

Jawless fishes ancestors of modern Jawless fishes ancestors of modern hagfishes and lampreys which hagfishes and lampreys which became extinct at the end of the became extinct at the end of the Devonian period, 360 years ago.Devonian period, 360 years ago.

Lamprey (Lampetra) on rainbow trout.

Hagfish

BibliographyBibliography• http://en.wikipedia.org/wiki/Fishhttp://en.wikipedia.org/wiki/Fish

• http://en.wikipedia.org/wiki/Priscacarahttp://en.wikipedia.org/wiki/Priscacara • http://en.wikipedia.org/wiki/File:Pacific_hagfish_Myxine.jpghttp://en.wikipedia.org/wiki/File:Pacific_hagfish_Myxine.jpg

• http://en.wikipedia.org/wiki/Hagfish http://en.wikipedia.org/wiki/Hagfish